Use an Apple USB-C Multiport Adapter. As I type this I have the adapter connected to my rMB, my iPhone 6 connected to the adapter, an HDMI-to-TV adapter connected to the adapter, and a USB-C charging cable connected to the adapter, and both my computer and phone are charging fine.

Having said that, I've read that the multiport adapter won't charge an iPhone 6+ properly, but I have no personal experience with that.

My only major gripe with the multiport adapter is that it won't charge anything connected to the usb-a port unless the usb-c port is connected to the Macbook. There have been a number of times I'd like to leave something connected and charging even when I am using the Macbook somewhere else.

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